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-rw-r--r--arch/m68k/kernel/process.c377
1 files changed, 375 insertions, 2 deletions
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
index 6cf4bd6e34f8..c54ef927e483 100644
--- a/arch/m68k/kernel/process.c
+++ b/arch/m68k/kernel/process.c
@@ -1,5 +1,378 @@
1/*
2 * linux/arch/m68k/kernel/process.c
3 *
4 * Copyright (C) 1995 Hamish Macdonald
5 *
6 * 68060 fixes by Jesper Skov
7 */
8
9/*
10 * This file handles the architecture-dependent parts of process handling..
11 */
12
13#include <linux/errno.h>
14#include <linux/module.h>
15#include <linux/sched.h>
16#include <linux/kernel.h>
17#include <linux/mm.h>
18#include <linux/slab.h>
19#include <linux/fs.h>
20#include <linux/smp.h>
21#include <linux/stddef.h>
22#include <linux/unistd.h>
23#include <linux/ptrace.h>
24#include <linux/user.h>
25#include <linux/reboot.h>
26#include <linux/init_task.h>
27#include <linux/mqueue.h>
28
29#include <asm/uaccess.h>
30#include <asm/system.h>
31#include <asm/traps.h>
32#include <asm/machdep.h>
33#include <asm/setup.h>
34#include <asm/pgtable.h>
35
36
37asmlinkage void ret_from_fork(void);
38
39
40/*
41 * Return saved PC from a blocked thread
42 */
43unsigned long thread_saved_pc(struct task_struct *tsk)
44{
45 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
46 /* Check whether the thread is blocked in resume() */
47 if (in_sched_functions(sw->retpc))
48 return ((unsigned long *)sw->a6)[1];
49 else
50 return sw->retpc;
51}
52
53/*
54 * The idle loop on an m68k..
55 */
56static void default_idle(void)
57{
58 if (!need_resched())
59#if defined(MACH_ATARI_ONLY)
60 /* block out HSYNC on the atari (falcon) */
61 __asm__("stop #0x2200" : : : "cc");
62#else
63 __asm__("stop #0x2000" : : : "cc");
64#endif
65}
66
67void (*idle)(void) = default_idle;
68
69/*
70 * The idle thread. There's no useful work to be
71 * done, so just try to conserve power and have a
72 * low exit latency (ie sit in a loop waiting for
73 * somebody to say that they'd like to reschedule)
74 */
75void cpu_idle(void)
76{
77 /* endless idle loop with no priority at all */
78 while (1) {
79 while (!need_resched())
80 idle();
81 schedule_preempt_disabled();
82 }
83}
84
85void machine_restart(char * __unused)
86{
87 if (mach_reset)
88 mach_reset();
89 for (;;);
90}
91
92void machine_halt(void)
93{
94 if (mach_halt)
95 mach_halt();
96 for (;;);
97}
98
99void machine_power_off(void)
100{
101 if (mach_power_off)
102 mach_power_off();
103 for (;;);
104}
105
106void (*pm_power_off)(void) = machine_power_off;
107EXPORT_SYMBOL(pm_power_off);
108
109void show_regs(struct pt_regs * regs)
110{
111 printk("\n");
112 printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
113 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
114 printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
115 regs->orig_d0, regs->d0, regs->a2, regs->a1);
116 printk("A0: %08lx D5: %08lx D4: %08lx\n",
117 regs->a0, regs->d5, regs->d4);
118 printk("D3: %08lx D2: %08lx D1: %08lx\n",
119 regs->d3, regs->d2, regs->d1);
120 if (!(regs->sr & PS_S))
121 printk("USP: %08lx\n", rdusp());
122}
123
124/*
125 * Create a kernel thread
126 */
127int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
128{
129 int pid;
130 mm_segment_t fs;
131
132 fs = get_fs();
133 set_fs (KERNEL_DS);
134
135 {
136 register long retval __asm__ ("d0");
137 register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
138
139 retval = __NR_clone;
140 __asm__ __volatile__
141 ("clrl %%d2\n\t"
142 "trap #0\n\t" /* Linux/m68k system call */
143 "tstl %0\n\t" /* child or parent */
144 "jne 1f\n\t" /* parent - jump */
145#ifdef CONFIG_MMU
146 "lea %%sp@(%c7),%6\n\t" /* reload current */
147 "movel %6@,%6\n\t"
148#endif
149 "movel %3,%%sp@-\n\t" /* push argument */
150 "jsr %4@\n\t" /* call fn */
151 "movel %0,%%d1\n\t" /* pass exit value */
152 "movel %2,%%d0\n\t" /* exit */
153 "trap #0\n"
154 "1:"
155 : "+d" (retval)
156 : "i" (__NR_clone), "i" (__NR_exit),
157 "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
158 "i" (-THREAD_SIZE)
159 : "d2");
160
161 pid = retval;
162 }
163
164 set_fs (fs);
165 return pid;
166}
167EXPORT_SYMBOL(kernel_thread);
168
169void flush_thread(void)
170{
171 current->thread.fs = __USER_DS;
172#ifdef CONFIG_FPU
173 if (!FPU_IS_EMU) {
174 unsigned long zero = 0;
175 asm volatile("frestore %0": :"m" (zero));
176 }
177#endif
178}
179
180/*
181 * "m68k_fork()".. By the time we get here, the
182 * non-volatile registers have also been saved on the
183 * stack. We do some ugly pointer stuff here.. (see
184 * also copy_thread)
185 */
186
187asmlinkage int m68k_fork(struct pt_regs *regs)
188{
1#ifdef CONFIG_MMU 189#ifdef CONFIG_MMU
2#include "process_mm.c" 190 return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
3#else 191#else
4#include "process_no.c" 192 return -EINVAL;
5#endif 193#endif
194}
195
196asmlinkage int m68k_vfork(struct pt_regs *regs)
197{
198 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
199 NULL, NULL);
200}
201
202asmlinkage int m68k_clone(struct pt_regs *regs)
203{
204 unsigned long clone_flags;
205 unsigned long newsp;
206 int __user *parent_tidptr, *child_tidptr;
207
208 /* syscall2 puts clone_flags in d1 and usp in d2 */
209 clone_flags = regs->d1;
210 newsp = regs->d2;
211 parent_tidptr = (int __user *)regs->d3;
212 child_tidptr = (int __user *)regs->d4;
213 if (!newsp)
214 newsp = rdusp();
215 return do_fork(clone_flags, newsp, regs, 0,
216 parent_tidptr, child_tidptr);
217}
218
219int copy_thread(unsigned long clone_flags, unsigned long usp,
220 unsigned long unused,
221 struct task_struct * p, struct pt_regs * regs)
222{
223 struct pt_regs * childregs;
224 struct switch_stack * childstack, *stack;
225 unsigned long *retp;
226
227 childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
228
229 *childregs = *regs;
230 childregs->d0 = 0;
231
232 retp = ((unsigned long *) regs);
233 stack = ((struct switch_stack *) retp) - 1;
234
235 childstack = ((struct switch_stack *) childregs) - 1;
236 *childstack = *stack;
237 childstack->retpc = (unsigned long)ret_from_fork;
238
239 p->thread.usp = usp;
240 p->thread.ksp = (unsigned long)childstack;
241
242 if (clone_flags & CLONE_SETTLS)
243 task_thread_info(p)->tp_value = regs->d5;
244
245 /*
246 * Must save the current SFC/DFC value, NOT the value when
247 * the parent was last descheduled - RGH 10-08-96
248 */
249 p->thread.fs = get_fs().seg;
250
251#ifdef CONFIG_FPU
252 if (!FPU_IS_EMU) {
253 /* Copy the current fpu state */
254 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
255
256 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
257 if (CPU_IS_COLDFIRE) {
258 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
259 "fmovel %/fpiar,%1\n\t"
260 "fmovel %/fpcr,%2\n\t"
261 "fmovel %/fpsr,%3"
262 :
263 : "m" (p->thread.fp[0]),
264 "m" (p->thread.fpcntl[0]),
265 "m" (p->thread.fpcntl[1]),
266 "m" (p->thread.fpcntl[2])
267 : "memory");
268 } else {
269 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
270 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
271 :
272 : "m" (p->thread.fp[0]),
273 "m" (p->thread.fpcntl[0])
274 : "memory");
275 }
276 }
277
278 /* Restore the state in case the fpu was busy */
279 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
280 }
281#endif /* CONFIG_FPU */
282
283 return 0;
284}
285
286/* Fill in the fpu structure for a core dump. */
287#ifdef CONFIG_FPU
288int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
289{
290 char fpustate[216];
291
292 if (FPU_IS_EMU) {
293 int i;
294
295 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
296 memcpy(fpu->fpregs, current->thread.fp, 96);
297 /* Convert internal fpu reg representation
298 * into long double format
299 */
300 for (i = 0; i < 24; i += 3)
301 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
302 ((fpu->fpregs[i] & 0x0000ffff) << 16);
303 return 1;
304 }
305
306 /* First dump the fpu context to avoid protocol violation. */
307 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
308 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
309 return 0;
310
311 if (CPU_IS_COLDFIRE) {
312 asm volatile ("fmovel %/fpiar,%0\n\t"
313 "fmovel %/fpcr,%1\n\t"
314 "fmovel %/fpsr,%2\n\t"
315 "fmovemd %/fp0-%/fp7,%3"
316 :
317 : "m" (fpu->fpcntl[0]),
318 "m" (fpu->fpcntl[1]),
319 "m" (fpu->fpcntl[2]),
320 "m" (fpu->fpregs[0])
321 : "memory");
322 } else {
323 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
324 :
325 : "m" (fpu->fpcntl[0])
326 : "memory");
327 asm volatile ("fmovemx %/fp0-%/fp7,%0"
328 :
329 : "m" (fpu->fpregs[0])
330 : "memory");
331 }
332
333 return 1;
334}
335EXPORT_SYMBOL(dump_fpu);
336#endif /* CONFIG_FPU */
337
338/*
339 * sys_execve() executes a new program.
340 */
341asmlinkage int sys_execve(const char __user *name,
342 const char __user *const __user *argv,
343 const char __user *const __user *envp)
344{
345 int error;
346 char * filename;
347 struct pt_regs *regs = (struct pt_regs *) &name;
348
349 filename = getname(name);
350 error = PTR_ERR(filename);
351 if (IS_ERR(filename))
352 return error;
353 error = do_execve(filename, argv, envp, regs);
354 putname(filename);
355 return error;
356}
357
358unsigned long get_wchan(struct task_struct *p)
359{
360 unsigned long fp, pc;
361 unsigned long stack_page;
362 int count = 0;
363 if (!p || p == current || p->state == TASK_RUNNING)
364 return 0;
365
366 stack_page = (unsigned long)task_stack_page(p);
367 fp = ((struct switch_stack *)p->thread.ksp)->a6;
368 do {
369 if (fp < stack_page+sizeof(struct thread_info) ||
370 fp >= 8184+stack_page)
371 return 0;
372 pc = ((unsigned long *)fp)[1];
373 if (!in_sched_functions(pc))
374 return pc;
375 fp = *(unsigned long *) fp;
376 } while (count++ < 16);
377 return 0;
378}